The present invention is related to filtering Mobile Application Part (MAP) short message service (SMS) messages for spam in signaling system 7 (SS7) mobile communications networks and will be described with specific reference thereto, although it will be appreciated that the invention may have usefulness in other fields and applications, such as other types of SPAM filtering of MAP SMS messages. With the advancements in communication technologies such as the Internet and wireless communications networks, the ability of people to communicate with one another has become seamless and largely ubiquitous. However, these same technological advances have made it easy for advertisers, hackers, etc. to send large amounts of unsolicited messages or spam to communications devices. Most Internet users are unfortunately all-too familiar with spam email and other similar nuisances. In addition to creating difficulties for the end users of such advanced communications systems, spam also occupies service provider resources, wherein spam email and the like has affected the revenue generation capabilities of Internet service providers generally. Further, spam can be used to attempt to defraud unsuspecting users by enticing users to provide credit card or other personal information. Beyond email type of spam, moreover, owners and commercial operators of wireless telecommunications networks must deal with SMS spam, wherein the provision of such short messaging services has heretofore provided another avenue for unscrupulous spammers to propagate spam. In the wireless telecommunications context, like that of the Internet, spam creates an uncomfortable user experience along with increased operational expenses for service providers due at least partially to increased SS7 network message traffic. Prior spam filtering attempts have focused on sorting out spam at the Short Message Service Centers (SMSCs or SMS-Cs) of the network, but this type of approach may be only partially successful in minimizing overall network traffic. Thus, there is a need for improved systems and methodologies for combating spam by which the associated network traffic and user dissatisfaction can be mitigated.